1. Field of the Invention
The present invention relates to an imaging apparatus and, more particularly, to an imaging apparatus having a zooming function.
2. Description of the Related Art
Broadly, the methods for enlarging and contracting images can be sorted into two types: namely, a type in which an image is optically enlarged or contracted by means of a zoom lens system, and a method in which an image is electrically processed through, for example, an image memory device.
The method which relies upon an optical image processing, however, is disadvantageous in that it requires a zoom lens system which is large and heavy. The method which electrically processes an image also suffers a problem that a complicated image processing system has to be employed.
In general, signals read from an imaging device have a component corresponding to a photoelectrically converted signal as well as a clock leakage component which corresponds to reading and shifting clocks. Both components are superposed on each other to form the output signal from the imaging device. When the signal read out from the imaging device is directly supplied to a monitor for display, the clock leakage component produces noise in the form of vertical stripes which seriously impairs the quality of the displayed picture. The signal output from an imaging device also includes a moire component which results from the sampling of image information. The moire component is also a factor which impairs the quality of the displayed image.